A new multilevel inverter topology with reduced switch count for solar PV power conversion [articol]

Abstract

Multilevel inverters can synthesize a high voltage staircase waveform with low and medium voltage components. A new multilevel inverter topology called Asymmetric Dual Source Multilevel Inverter (ADS-MLI) is proposed. When compared to the topologies found in literature, it can produce multiple levels in the output voltage with less number of power switches. Most of the topologies found in the literature require cascading feature to achieve asymmetric operation; but the ADS-MLI can operate without the need for cascading. Further it requires only two independent DC sources to produce multiple levels in the voltage waveform. The independent sources can be two independent Solar Photo Voltaic (PV) strings. A simulation prototype capable of synthesizing 13 levels fed by Solar PV strings is developed in MATLAB Simulink environment. Its performance is observed in the aspects of number of switching components, efficiency, THD and its efficiency is compared with other topologies. The performance of simulated ADS-MLI is validated with a 1 kW prototype fabricated using FGA25N120-ANTD fed by an Ecosense Solar PV emulator and controlled by FPGA-SPARTAN 6 processor.